Building construction



May 2s, 193s.

Filed NOV. 18, 1951 INVENTOR.

A TTORNEY.

Patented May 28,

UNITED STATES PATENT oFFlcE BUILDING CONSTRUCTION Maui-ice o. nose-num, Philadelphia, Pa.

Application November 18, 1931, Serial No. 575,829

7Claim8.

This invention relates to building constructions and particularly to acoustical building constructions.

. It has been proposed heretofore to provide a sheet metal pan with perforations drilled or punched in the face as the finishing exposed element of an acoustic treatment. Such pans were filled with sound absorbing materials and, in addition to being diicult of application, were possessed of certain disadvantages. The sheet metal employed was possessed of a resonance response which was highly undesirable, was subject to corrosion and rust, and was an electrical conductor necessitating great care in us'e in ceilings adjacent lights or conduits. Such sheet metal devices were difficult to work as they were not readily susceptible to curved forms nor capable of quick and easy cutting to accord with small areas to be treated or fitted as when working around columns and the like, and were primarily adapted for ceilings only and were not well adapted for use for side walls. The metal pans after punching were of substantially fixed acoustic properties and were susceptible to buckling, warping, and twisting, and formed an uneven, non-uniform surface. They also formed a poor base for subf sequent painting operations as the paint fllm frequently became loose at the edge of the perforations unless the paint was baked on prior to application, and if it became chipped or rusted was diflicult to refnish.

This invention contemplates the provision of Y ya molded, apertured, reinforced, initially plastic butsubsequently hardened material and a process for molding and treating same.

It is among the objectsof the invention; to

'provide anacoustic tile block as the exposed ceptible to facile sub-divisions, and in which sound transmitting properties may be varied; to

vide a tile block of attractive superficial aspect;

to provide a frangible tile with resilient anchoring devices; and many other objects and advan- (cl. '1a-1s) tages as will become more apparent as the de? scription proceeds.

In the accompanying drawing:

Fig. 1 represents a transverse vertical section through the mold of this invention with a tile in 5 operative molded relation thereto,

Fig. 2 represents a fragmentary vertical section through a section of the finished tileand of the flexible mold disclosing the manner of disassociation of the two, 10

Fig. 3 represents a plan of a completed tile showing in dotted lines the reinforcing ribs on the rear face thereof,

Fig. 4 represents a fragmentary bottom plan of two juxtaposed tiles showing the disposition 15 of the resilient locking lugs of each tile,

Fig. 5 represents a vertical section through an assembly of a plurality of tiles with the furring strips to which they are attached, with sound absorbing material in position behind the tiles, and 20 showing the possible variations in the superficial aspect obtained by filling the space between adjacent tiles with the same or similar cementitious material as that with which the tiles are constructed toward the bottom of the figure,

Fig. 6 represents a fragmentary perspective of a pair of juxtaposed tiles,

Fig. 7 represents a similar perspective in which the line of jointure between tiles has been oblityerated by a wedge of plaster subsequentlysanded 30 `off to give a smooth finish, and

Fig. 8 represents a similar perspective in which the surface of a tile assembly has been given superficial markings simulating apertures in spaces in which there are no real apertures to im- 35 part a uniform superficial aspect to the whole. The preferred form of tile of this invention comprises the block I0 having, preferably, four apertured areas Il separated by thin ribs I2 on the lower side of the block merging with the pe- 40 ripheral or edge rib or reinforcement I3. It is `important to note that the ribs l2 on the under side of the block, while adequate to reinforce the lrigid unit, are so small as to have no adverse effect on the sound transmitting properties of the apertures to be described. In other words, thel wave form entering the apertures in the aper-y tured area to contact with the absorbing material behind the area, is inappreciably affected by the reinforcing rib. Each apertured area comprises a series of inwardly tapering apertures Il extending from the outer exposed face of the tile block to the inner surface of the block. The taper of each aperture while preferably rather slight serves two functions, in that it minimizes J the finished Wall.

contact; of the sound energy with the sides of the apertures and also serves the important purpose of providing enlargement of the exterior diam-` eter of each aperture when the block is sanded down or otherwise treated to render it thinner than as initially formed. 'I'his feature of the apertures is of importance as it enables the visual aspect of the aperture to be very small While those on the/ceiling n iay vary between large and small according to the ceiling height. Either side wall or ceiling apertures being variable as to exposed orifice diameter according to acoustic requirements as well. Of course, for certain purposes, it is contemplated that the apertures may be untapered or cylindrical. Obviously also, the apertures may if desired be closed by application of a skim coating of plaster.

The mold according to this invention comprises a base 1, removable side elements 8 and a flexible mat 9 removably disposed on the base 1. 'Ihe removable side pieces 9 preferably are undercut as shown to form the bevelled edges 6 at the outer peripheral portion of the tile if such bevelled edge is desired. 'I'he resilient mat 9, which is preferably of rubber, has a cruciform channel or groove I5 dividing the mat into four similar areas I6, and each such area is provided with a plurality of vertically extending or upstanding nibs, generally -of truncated conical form as shown at I1. The nibs may be cylindrical if desired. These nibs may be arranged in any desired pattern and may be of such length as desired. It is of importance, however, that they at least be formed of resilient material such as rubber, so as to be susceptible to flexing. The provision of the mat 9 and nibs I1 of flexible rubber has been found satisfactory for the purpose.,

With the mold in the position shown in Fig. 1, the exposed surfaces of the mat and nibs are coated with a lubricant such as grease, oil, or soap, or the like, then cementitious material in a more cr less uid state is poured into the mold to a level just about at the end of the respective nibs I1. The cementitious materials may be plaster of Paris, acoustic plaster, or any other cementitious material which hardens when set, but preferably which is somewhat friable so as to facilitate abrasive responsiveness. For certain purposes it may be desired to use clay which may be baked or otherwise treated to secure a hardening action. Excellent` results have been obtained from plaster which sets quickly so that the tile may be removed from the mold after a fairly short time interval. This removal is accomplished by removing the side strips 8 and the base 1, then by seizing the end of the mat 9 and pulling it outwardly and downwardly as shown in Fig. 2, the entire mat is quickly stripped from The rubber stretches slightly, owing to the lack of adhesion of the block to the nibs due to the lubricant, and, possibly due to a slight shrinkage of diameter of the nibs when the rubber mat I6 is stretched, and is instantly withdrawn.

After the block or tile has been cast any roughness and any inequalities of the exposed surface may be quickly removed by a sanding or abrading or grinding operation, which makes the surfaceuniform, smooth and ornamentally attractive. This, as noted, is facilitated, by providing a tile which while being frangible is also somewhat friable. I'he abrading step also has the effect of equalizing the diameter of the surface end'of the apertures in a. given tile.

1t is obvious that the tiles so made may be kholes I8 drilled in the easily Worked tile.

attached in any desired manner as by any desired form-of attachment, but for ease and quickness of assembly it is preferred that some such device be provided as the resilient locking lugs shown in Figs. 4 and 5. These or similar lugs may be attached in any desired manner, but owing to the peculiarly desirable characteristics of the cementitious friable tile the lugs disclosed are quickly and easily attached by means of It will be understood that the tile formed of plaster, although being hard and permanent is fairly friable, such as to respond readily to abrasion as by rubbing with sandpaper, so as to be quickly and easily smoothed or reduced in thickness, and can readily be drilled or sawed or otherwise worked in accordance with conditions. For additional strength the tile may have reinforcing rods or strands embedded in it between apertures. Each tile preferably carries two lugs oppositely but asymrnetrically disposed relative the median line so that while one lug may be (for instance) one inch from a side edge, the other opposite lug might be two inches from the sidevedge so as to permit staggered engagement of the lugs on juxtaposed tiles for engagement with the same furringl strip, to be described, and as shown in Figs. 4 and 5. 'Ihe tiles are preferably sanded to the proper thickness for requirements so far as previously ascertainable, and' then each tile is I drilled transversely through the outer reinforcing bead I4 on lines coextensive with the inner surface of the tile so that the two legs 2D of a locking lug 2I may be laterally inserted to a positionv overlying the inner or under surface of the tile. Perpendicular intersecting grooves 22 may be formed in the edge of the tile to receive the perpendicularly extending shanks 23 flush with the edge. The free resilient end of each lug 2I includes the outwardly i'lared portions 24 joined in acute angular relation to the hook 25 arranged to engage over the lip of a furring strip. The free ends of the lug 2I comprised of legs 20 preferably are spaced from the inner surface of the tile by a layer of mesh material 26 bentv about the legs for locking engagement with the mesh material, forming a bearing surface to distribute the strain over an appreciable area of the tile. As the spring lugs are inserted laterally and held frictionally only (preferably) they are quickly and easily attached and detached, but are not removable when adjacent edges of tiles are in substantial abutment, as they are when mounted. Of course the resilient locking lugs may be molded into the tile if desired. v

, Obviously the holes-I8 and grooves 22 may be cast in the tile at the time of casting of the tile itself if desired. Also obviously as many attaching devices as may be necessary maybe used.

. It is contemplated that the resilient locking lugs will be separately formed and shipped, so that the tiles may be shipped Hat, to the work or job, and then the spring lugs may be attached to the individual tiles before connection to the furring strips. This facilitates packing and shipping and, to a large degree, obviates breakn age.

In orderto attach the tiles, furring strips are provided which-are suitably mounted in properly spaced relation and each strip 21 includes the inwardly sloping faces 28 and the lips 30. With the furring strips arranged in parallel alignment either on a ceiling or side wall, it will be obvious that the attachment of the tiles simply involves pushing the resilient locking lugs inwardly against'the tapering guiding suriace 28 to resilient hooked engagement of the'hook 2l over the lip 3l as shown in Fig- 5. a

While each tile may be packed with a suitable quantity of sound absorbing material such as mineral or rock wool, whether granulated or nodulated, or felt, or other fibrous or other sound' absorbent material, prior to its being attached to its furring strips, yet it is a part of this invention to provide a series of tiles to the furring strips, upon which insulating or sound absorbing material is thrown, or blown or otherwise applied to a suitable depth as shown byk 32, in Fig. 5. Obviously the depth of sound absorbent material may be varied in accordance with conditions and according to the requirements of the particular compartment being treated. a a a It is of importance to note that so far as the use of the tile of this invention isconcerned it makes no difference whether itis af ceiling or a side wall which is treated as the material can be dumped in behind it safely as the tiles are applied, and the superficial aspect of the tile is suitable for application to side walls.

It has been observed that the edge of each tile is preferably chamfered or bevelled to provide a satisfactory finish or line of demarkation when the tiles are juxtaposed as shown in Fig. 6 and the upper part of Fig. 4, and the panelling effect thus produced is satisfactory for some purposes and forms an economical assembly. As shown, however, in Fig. 'l and the lower part of Fig. 5 the V-shaped channel provided by the divergence of the bevelled edges 6 may be filled with plaster as in the wedge shaped plaster insert 3l shown in Figs. 7, 8 and the lower part of Fig. 5, which, when set, may be suitably sandpapered or otherwise abraded to form a smooth homogenous over-all finish which is highly desirable, especially for side wall purposes. The visual aspect being of a smooth uniform level plaster wall with regular yseries of ornamental designs in small apertures.

To enhance the over-all effect and the homogeneity of the assembly, it is contemplated to provide a stippling or stencil pattern of dots or spots 32, simulating the external appearance ofthe true apertures Il in the area which is not apertured, as shown in Fig. 8.

It will be appreciated that the tile are subject to wide variations in size, and in superficial aspect and that the chamfered or bevelled edges 6 instead of being flat and smooth as shown may be serrated and curved in order to facilitate bond with the subsequently applied plaster 3l, to more clearly avoid any line of jointure between the molded and the plastered surfaces.

It will be appreciated that the plaster, comprised as it is of multitudinous minute but rough particles, furnishes an excellent bond for any coating of paint or enamel that may be applied thereto.

It will be understood that the non-resonating characteristic of the tile of this invention is of particular importance in acoustic treatments, where, despite the effort to preclude reflection by providing a high degree of sound absorption, it has frequently been found that the association of a resonating surface in the treatment has resulted in such resonance (by co-vibration with the source of sound) as substantially to nullify the effect of the treatment. This is obviated due to the rigid character of the tile and by its practically complete absence of elasticity. The tiles of this invention are crystalline and non-elastic, in contrast to the amorphous characteristics of previous devices. For further development of resonance in acoustic treatments, yreference is made to my earlier Patent No. 1,609,811, dated December 7, 1926.

The tile may be formed in large numbers, sanded and finished to the proper thickness, painted or enamelled as desired and then shaped to `be worked as completed unit's so that a minimum of labor is required at the job.

In addition to the advantages previously pointed out, it maybe emphasized that the tile is even more fireproof than the metal pans, and are not affected by moisture as are the metal receptacles and therefore may be used in natatoriums and in .Y seashore structures where the metal pans would be unavailable.

In my former applications Ser. Nos. 420,668, filed January 4, 1930, and 456,364, filed May 28, 1930, there was disclosed building constructions in which the external exposed portion of the acoustic assembly was comprised of `a multiple membrane, and specifically that this multiple membrane included a rigid self-sustaining apertured sheet, to which a woven membrane was secured,` as by pasting or the like, and soarranged that the apertures were masked or concealed by `the woven membrane, but without any appreciable diminution in sound transmitting effect. It is contemplated that the tile of this invention may form the rigid, self-sustaining, apertured element to which a woven membrane may be attached to form a multiple membrane, either after application of a series of tiles with subsequent plastering (if necessary) to form a continuous surface, as by pasting a membrane continuous over a plurality of tiles, or prior thereto as individual units, in accordance with the teachings of a former application of Stanley H. Rosenblatt and Maurice C. Rosenblatt, resulting in Patent No. 1,819,039, in which a membrane was applied to a unit, with the membrane prolonged past two edges for subsequent pasting to adjacent unit membranes, to obliterate the line of jointure between units.

It is also contemplated that instead of depositing sound absorbing material on the tiles, it may be supported in spaced relation thereto in accordance with the teachings of the recited applications on building constructions.

It will be observed that the disassembly of an acoustic treatment including these tiles requires destruction of but one tile of an area to be able to detach all subsequent tiles in that area, as will be obvious. It will be obvious that owing to the cementitious character of the tiles any irregularities existing around columns and the like may be accounted for by sawing a tile to the required dimensions, or by simply plastering to fill the void.

I claim as my invention:

l. An acoustic block comprising a hardened i sion, and having a plurality of tapering apertures extended completely through the material -and so arranged that decrease in thickness of the sheet abut the furring strip, a resilient lug separably engaging the tile extending through the bead to contact with the tile surface adjacent the bead, andextending'beyond the bead perpendicularly of ythe tile, a lip on the furring strip and a hook on the lug arranged for interlocking engagement when the bead is abutting the strip.

4. In a building construction, a wall surface comprised of a plurality of cementitious tiles, each comprising a thin sheet having reinforcing ribs formed in the sheet and having a pluralityt of apertures formed in the sheet adjacent the ribs, each tile having a bevelied edge, the tiles disposed in abutting engagement with the hevelled edges forming an outwardly flared groove. a cementitious plug mounted in the groove in bonded relation to each tile to form an over-all superficial continuous surface.

5. In acoustic treatments, a plurality of acoustic tiles each comprising a hardened sheet of cementitious material having a plurality of apertures extending through a sheet from one surface to the other, the tiles disposed in abutting edge relation to form a line of jointure between them, plaster disposed in the line to conceal the line of jointure between the tile and to give a superficial 'aspect as to a continuous over-all surface. `f

6. An acoustic tile, comprising a hardened sheet of cast plaster having intersecting reinforcing ribs on one-surface and a reinforcing bead surrounding the tile on the same surface. a plurality of tapering apertures extending through the sheet and tapering from the first mentioned surface to the other between the ribs and the bead.

7. An acoustic block comprising a hardened sheet of cementitious material having an outer sound Wave receiving surface and an inner surfacel arranged for concealment in use, means distinguishing the inner and outer surfaces to preclude satisfactory reversal, the block having a plurality of tapering apertures extending through the sheet from one surface to the other. said apertures arranged with their larger ends in the inner subsequently concealed surface and having small ends in the surface to be exposed to the sound waves. I

MAURICE C. ROSENBLATT. 

